Judges 11:12-15, 32-33

Then Jephthah sent messengers to the king of Ammon to ask, “What is your quarrel with us? Why have you invaded our country?” The king of Ammon answered Jephthah’s messengers, “When the Israelites came out of Egypt, they seized my land from the River Arnon to the River Jabbok, as far as the River Jordan. Now give it all back, and we’ll be at peace.” Jephthah again sent messengers back to the king of Ammon with this answer: “Israel seized neither the land of Moab nor the land of Ammon.

So Jephthah crossed the river with his men to fight the Ammonites, and YAHWEH gave him victory. He struck at them from Aroer to the area near Minnith, twenty villages in all, and as far as Abel Keramim. The Israelites brought the Ammonites down to the dust in a great slaughter.